The present invention relates to a method of analyzing data of a plasma processing apparatus for processing a semiconductor wafer through plasma, a plasma processing method, and a device used for the plasma processing method.
In order to obtain the micro shape of the semiconductor device to be formed on the wafer, plasma processing such as an etching process is performed for bringing a substance into an ionized state (plasma state) so as to remove the substance on the wafer through its action (reaction on the wafer surface).
The plasma processing apparatus such as the etching apparatus for processing with plasma is equipped with a spectroscope (OES: Optical Emission Spectroscopy) which allows monitoring of the plasma light in order to cope with light emission resulting from ionizing phenomenon caused by the plasma. The data measured by the spectroscope will be referred to as OES data.
In order to stabilize the micro shape of the semiconductor device, the etching apparatus is structured to apply control technology to measure the OES data, predict etching processing results such as dimension of the micro shape, and adjust the etching processing condition.
It is necessary to predict the etching processing results with minimum error by using the OES data for stabilization of the etching processing result.
There is a known method of predicting the etching processing result as disclosed in JP-4547396.
JP-4547396 discloses the method of predicting the etching processing result by selecting monitor data and the corresponding time interval which are used for predicting the etching processing result from monitor data of the apparatus, including the OES data, and predicting the etching processing result using values only of the selected monitor data and the time interval, and the method of adjusting the etching processing condition in accordance with the prediction result.